1. Field of the Invention
The present invention relates to a printing device using an inkjet head, and more particularly to an ink injection method and apparatus that prevents erroneous pattern printing caused by vibration of a stage of the inkjet head.
2. Description of the Related Art
An inkjet head requiring high-accuracy positioning employs a linear motor as a driving source of its stage, and a base for placing the stage thereon is installed on a bottom using an anti-vibration means for eliminating vibration from the bottom.
Accordingly the base is placed in an unstable form, so, when the stage is operated, the stage is vibrated due to a repulsive force occurring in a direction opposite to the driving direction.
This vibration shakes the inkjet head installed to the stage, so patterns injected by the inkjet head are also shaken corresponding to the vibration.
Seeing it in more detail with reference to FIG. 1, a vibration caused by movement of a stage is generally generated at an initial ink injection, so a portion printed by initially injected ink is generally shaken due to the vibration.
As a technique for solving this problem, there is Korean Patent Application No. 10-2004-0059486, entitled “Repulsive force processing system for a stage device”.
This document discloses a repulsive force processing system including a propulsive force generating means for generating a propulsive force to offset a repulsive force applied to a base, and a control means for controlling a gain adjustment means for adjusting a gain of the propulsive force generating means.
However, though a propulsive force is generated to remove vibrations according to the above technique, there is a limit in completely eliminating the vibrations generated in an initial process.
Referring to FIG. 2 showing a vibrating status of the stage, the stage is abruptly vibrated in an initial moving process of the stage, and then these vibrations are reduced as time goes.
However, the conventional repulsive processing system requires a predetermined time to detect movement of the stage and generate a propulsive force, so it cannot rapidly remove the vibrations abruptly generated in an initial moving process of the stage.
Thus, there is an urgent need for a technique capable of solving the conventional problem that printed patterns are spoiled due to vibrations abruptly generated in an initial moving process of the stage.